Can you find the odd number in the following?

2716, 4135, 5321 and 7145

The first person saw the bridge step on it and crossed,
the second person saw the bridge did not step on it but crossed,
the third person did not see the bridge did not step on it but crossed.
Who are these people?

A professor thinks of two consecutive numbers between 1 and 10.
'A' knows the 1st number and 'B' knows the second number

A: I do not know your number.
B: Nor do I know your number.
A: Now I know.

What are the four solutions for this?

If 5 cats catch 5 mice in 5 minutes, how long will it take one cat to catch a mouse?

John asked Jack, "The time right now is 7 pm. Can you tell me what will be the time 23, 999, 995 hours later ?"

While Bella does not know the answer, do you ?

I’m tall when I’m young, and I’m short when I’m old. What am I?

A frog is at the bottom of a 30-meter well. Each day he summons enough energy for one 3-meter leap up the well. Exhausted, he then hangs there for the rest of the day. At night, while he is asleep, he slips 2 meters backwards. How many days does it take him to escape from the well?

I noticed one of the words in the oxford dictionary is spelled incorrectly. What about you?

I can write cow in 13 letters.

Can You?

Which statement is true out of the following?
One statement here is false.
Two statements here are false.
Three statements here are false.